In the prior art, it has already been proposed to provide systems in which the electrical energy coming from a supply source is distributed towards the electrical loads as a function of commands given, typically by the driver of the vehicle. However, these prior art arrangements have a certain number of drawbacks which the present invention proposes to overcome.
In the prior art arrangements for power supply in vehicles, the number of power supply and control wires is high, and this imposes a considerable penalty, in terms of both the overall cost of the electrical parts of the vehicle and to the technical complexity of the power supply system.
In addition, the prior art arrangements require to be perfectly matched with the various electrical function devices in the particular vehicle in which they are installed. For this reason, in the prior art, power supply arrangements are in general designed specifically for only one type of vehicle. In particular it is often necessary to redesign a large part of the electrical supply system, even when, in a vehicle of one given type or model, equipment options are only slightly different from the arrangements provided in the basic model.
Furthermore, the prior art vehicle electric supply arrangements usually include, starting from a circuit board, a certain number of plug-in components, and require a large number of connections for distribution in the system. This proliferation of connections is a major cause of the high cost of the system, and in addition it leads to a reduction in its reliability.
In the specification of European published patent application EP 0 181 534A, a system has been described which includes a central electrical unit for the centralised connection of electrical components such as cable harnesses, plug-in connectors, fuses and interruptors, these latter being typically in the form of relays, which are connected together through appropriate connecting layers. However, distribution of the power supply, or interconnection between specific modules linked to a circuit board, is not made possible by such an arrangement.